Bronze Casting with Dartmoor Arts

Back in August I was lucky enough to be offered the opportunity to spend a week on Dartmoor learning a pre-industrial Bronze Casting technique called Luted Crucible.

The course was organised by Dartmoor Arts, and run by Piers Watson who spent time living with a community in Indian learning and mastering the technique.

I was excited to learn this method of metal-casting for two reasons. Firstly, it uses all natural materials which can be found and collected just about anywhere, so it’s entirely possible to replicate this technique at home. Also as an archaeologist I am fascinated by ancient technologies, something which I want to bring into my jewellery making.

In this blog I’m not going to give you a blow-by-blow account of the technique, you can check out Piers’ website for more information on that, and if you want to learn further I’d highly recommend booking onto a course. Instead I am presenting a photo-journal of the week, so you can get a glimpse into what I got up to!

I spent the week living in a tent in the small Dartmoor village of Drewsteignton, something which I hadn’t done for years. I’m not going to lie it was cold, and I was pretty happy to get back to civilisation at the end of the week, but what I didn’t realise at the time was quite how weary I’d grown of city-life, and how much I was craving an escape into the middle of nowhere. And with no mobile phone coverage and a walk to the course each morning across corn fields, an escape is exactly what I got!

The Luted Crucible is what’s known as a ‘lost-wax’ casting technique, using inversion to pour the metal into the mold. This means that the desired object to cast is first made out of wax, then the mold is formed around the donkey-poop core using different mixtures clay and a silica-rich material (rice husks in this case), which has a very high melting point. The crucible itself, which holds the metal, is actually attached to the bottom of the mold. During firing, the wax melts & turns to gas which leaves via the porous clay, leaving a hollow void in it’s place, and once the bronze has reached a certain temperature (hot!) the whole crucible is inverted so the molten metal fills the void left by the wax.

Here are some of the various stages of making and drying the mold. The picture on the right shows the crucible containing copper and tin which meld in the furnace to form Bronze.

It was great spending time on a Devon farm where the workshops where situated, and meeting people from all different backgrounds. Amongst other people on the course I met a woman who has worked in foundry’s across London, and a chap who currently works as a stone-mason for the artist & sculpture Peter Randall-Page, one of the founders of Dartmoor Arts.

We used two kinds of furnace – a portable one which Piers had already made, and a pit-furnace which we made on the day.

Once air was blown through the furnace it got extremely hot, nearing 1000 Degrees Celsius. I did get the opportunity to get dressed up in the protective garb and keep guard of the fire whilst my pieces were in, but Piers did a great job of managing the process, which will take a lot of practice to make perfect.